Design Optimized CMOS Compatible Hybrid Silicon MIM Waveguide Cavity for Label Free Sensing

Alireza Khalilian; Hima Nikafshan Rad

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arXiv · 2508.18291

Design Optimized CMOS Compatible Hybrid Silicon MIM Waveguide Cavity for Label Free Sensing

Alireza Khalilian·Hima Nikafshan Rad

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Abstract

We numerically design a hybrid plasmonic dielectric refractive index biosensor comprising ametal insulator metal (MIM) bus waveguide evanescently coupled to a silicon core resonator. The geometry is optimized with a genetic algorithm (GA) using Ansys Lumerical FDTD simulations, targeting maximal sensitivity and figure of merit while minimizing the resonance linewidth. The optimized device achieves a sensitivity of 1276 nm/RIU, a full width at half maximum (FWHM) of 11.89nm, a quality factor of 221, and a figure of merit of 107 RIU1 (defined as S/FWHM). These results demonstrate precise discrimination of small refractive index variations and support the sensors applicability to label free biochemical and medical diagnostics.

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Alireza Khalilian, Hima Nikafshan Rad. 2025-08-21. Design Optimized CMOS Compatible Hybrid Silicon MIM Waveguide Cavity for Label Free Sensing. https://arxiv.org/abs/2508.18291

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